Heater Unit Series Two early model heater only
Problem I have is figuring the 'set' position of some of the internal flaps of the heater. (see pictures) I am not sure (a) if the wire original wire had a spring at either end or just one at the left as in the diagram, and (b) whether the armature is in closed or open position when the pulley tension in pulled left or right (or knob position at top or bottom). This armature effects the lower flap near the floor of the unit but-

I cannot figure whether having the FLAP CLOSED stops HOT AIR traveling into the cab of the car OR whether having the FLAP OPEN dilutes the hot air with a cold intake to reduce heat.

I can imagine it could be doing either. The knob set to top is HOT and set to bottom is VENT.


the armature as positioned with the lower/floor flap inside the heater in it's CLOSED position

the armature as positioned with the lower/floor flap inside the heater in it's OPEN position

 

I think that when you turn the engine OFF, the servo returns the flaps to OFF or NEUTRAL position.

in my Series 3, the flaps in the blower cases return to closed position when I turn the engine OFF even if I shut the engine with the a/c switch ON, But the Defroster flaps open. Try and figure that.

 

with this being a primitive series 2 early heater only option it seems a bit less developed than that. has me muddled at any rate.

 

sat this aside for a bit. looking again and still cant figure the exact underlying logic of the lower flap, whether it is directing heat or diluting it with cool air.